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After the violent earthquake that shook Los Angeles in 1994, earthquake scientists had new

s to report: The damage and death toll could have been much worse. More than 60 people died in this earthquake. By comparison, an earthquake of similar intensity that shook America in 1988 claimed 25 ,000 victims.Injuries and deaths were relatively less in Los Angeles because the quake occurred at 4:31 a. m. on a holiday, when traffic was light on the city’s highways. In addition, changes made to the construction codes in Los Angeles during the last 20 years have strengthened the city ’ s buildings and highways, making them more resistant to quakes. Despite the good news, civil engineers aren’t resting on their successes. Pinned to their drawing boards are blueprints for improved quake - resistant buildings. The new designs should offer even greater security to cities where earthquakes often take place.
In the past, making structures quake - resistant meant firm yet flexible materials, such as steel and wood, that bend without breaking. Later, people tried to lift a building off its foundation, and insert rubber and steel between the building and its foundation to reduce the impact of ground vibrations.
The most recent designs give buildings brains as well as concrete and steel supports. Called smart buildings, the structures respond like living organisms to an earthquake’s vibrations. When the ground shakes and the building tips forward, the computer would force the building to shift in the opposite direction. The new smart structures could be very expensive to build. However, they would save many lives and would be less likely to be damaged during earthquakes.
One reason why the loss of lives in the Los Angeles earthquake was comparatively low was that ______.
A.new computers had been installed in the buildings
B.it occurred in the residential areas rather than on the highways
C.large numbers of Los Angeles residents had gone for a holiday
D.improvements had been made in the construction of buildings and highways
The function of the computer mentioned in the passage is to ______.A.counterbalance an earthquake’s action on the building
B.predict the coming of an earthquake with accuracy
C.help strengthen the foundation of the building
D.measure the impact of an earthquake’ s vibrations
It can be inferred from the passage that in minimizing the damage caused by earthquakes attention should be focused on ______.A.the increasing use of rubber and steel in capital construction
B.the development of flexible building materials
C.the reduction of the impact of ground vibrations
D.early forecasts of earthquakes
The main purpose of this passage is mostly to______.A.compare the consequences of the earthquakes that occurred in the U. S.
B.encourage civil engineers to make extensive use of computers
C.outline the history of the development of quake - resistant building materials
D.report new developments in constructing quake - resistant building
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Scientists said they have found evidence of a gian...

Scientists said they have found evidence of a giant planet far out in our solar system.In a statement, the California Institute of Technology—Caltech—said this planet travels a very strange “longandthin orbit in the distant solar system.”The discovery was made by two researchers at Caltech: Konstantin Batygin and Mike Brown. They used mathematical modeling and computer simulations (模拟) to find the planet.So far, there have not been any direct observations of the planet. “My jaw hit the floor, ” said astronomer (宇航员) Mike Brown, the moment he realized there might be a ninth planet.
The scientists said it would take this planet 10,000 to 20, 000 years just to make one full orbit around the sun. The new planet, called “Planet Nine ” , has a mass about 10 times the size of Earth.If they are right, the newly found planet would be the ninth planet in our solar system. Pluto (冥王星) had been called the ninth planet until 2006, when it was renamed a “dwarf planet.”
Actual confirmation of a ninth planet would be very big news. “This would be a real ninth planet,” Brown said in the statement. “There have only been two true planets discovered since ancient times, and this would be a third. It&39;s a pretty substantial chunk of our solar system that&39;s still out there to be found, which is pretty exciting.”
While they did not get a picture of “Planet Nine ” yet, the scientists say they are using the biggest—and best—telescopes on Earth to try to find “Planet Nine. ” They are also working on improving their computer simulations. They want to find out more about “Planet Nine’s” orbit, and its impact on the outer part of our solar system.
The newly-found planet ________.
A.moves around the Sun
B.was discovered by two astronomers
C.travels a round orbit
D.is far away from our solar system
The possibility of finding a ninth planet made Mike Brown ________.A.confused
B.frightened
C.satisfied
D.surprised
According to the scientists, ________A.the planet is ten times larger than the Earth
B.ittakes the planet less than 10, 000 yearsto make a full orbit
C.Pluto was once thought to be the ninth planet in the solar system
D.Pluto was given anew name after it was discovered in 2006
It can be inferred from Paragraph 4that ________.A.there is no actual confirmation about the ninthplanet
B.no true planets were discovered in ancient times
C.scientists have found three planets in modern times
D.the ninth planet is the only one discovered since ancient times
To find“Planet Nine”, scientists are using allthe followingEXCEPT ________.A.mathematicalmodeling
B.computer simulations
C.advanced telescopes
D.large spacecrafts
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